Answer me this...

[jon]

Now its november, the days are getting colder and winter is approaching. I was taught at school that winter comes once a year because the earths trajectory around the sun isn't perfectly round, its slightly oval, so for a few months of the yearly orbit we are further away from the source of heat and thus cooler.

I know that the earth spins on its own axis once every 24 hrs to create day and night, and it orbits the sun once every 365 ish days to create a year, but how come australia has their winter in july and their summer in december??? Surley in December they are just as far away from the sun as we are (minus the diameter of the earth, which is fek all when considering these distances)?
how come the whole planet isnt colder when it is further from the sun and hotter when it is nearer?

[adeejaysdelight]

First of all Jon, the  diameter of the earth is very significant for us mere mortals. A change of just 10 degrees can make a big difference to us. And if you think about it, from equator to pole (which is just 12,000 or so miles) there is 100 degree tempreture difference at any given time.

As to your question, the earth does not sit on a vertical axis, it is at a 30 degree lean angle (roughly) meaning that either the top half or bottom half of the sphere is closer to the sun. Only my a few thousand miles, but as highlighted above, This makes a significant difference. Obviously is does not oppererate like a swithch either, which is why we get the other seasons, as out location slowly moves closer or farther away from our heat source.

There is a lot of stuff about this sort of thing on YouTube.

[richfzs]

Being closer to, or further away from, the sun has got foc all to do with it. The difference, in percentage terms, is tiny.

What is important, is the tilt from the vertical axis. Think on a beam of light, and for arguments sake, every beam of light is a foot wide. When that beam of light is aimed squarely at a surface, it covers an area a foot wide - but if you start to tilt the surface it's hitting, it suddenly covers a bigger area. So the energy it contains is spread thinner, less energy for a given area, hence it's cooler.

When we're tilted towards the sun, we have summer, and vice versa.

[Nosobrut]

While we're on this subject, how fast would we have to travel to keep riding into a never ending sunset

[keithfzs1000]

It depends on your altitude above sea level and the latitude of your location. At the equator and at sea level, you would have to be traveling slightly over 1000 miles per hour or about Mach 1.4. This is obviously beyond the capability of the fazer even if it is ivanised  :rollin :rollin :rollin :rollin

[risticuss]

Typing "why do we have seasons" into Google brings up a wealth of images to illustrate the point, as sometimes things can get lost in the explanation. I'm one who needs images to explain something so here's a link to one.


http://d1jqu7g1y74ds1.cloudfront.net/wp-...ations.jpg


Hope it helps

[Liroka]

Being closer to, or further away from, the sun has got foc all to do with it. The difference, in percentage terms, is tiny.

What is important, is the tilt from the vertical axis. Think on a beam of light, and for arguments sake, every beam of light is a foot wide. When that beam of light is aimed squarely at a surface, it covers an area a foot wide - but if you start to tilt the surface it's hitting, it suddenly covers a bigger area. So the energy it contains is spread thinner, less energy for a given area, hence it's cooler.

When we're tilted towards the sun, we have summer, and vice versa.

In addition, the northern hemisphere is also closer to the sun during 'our' winter.

[fazersharp]

So after all this physics------------------------- do I get my winter gloves out yet?

[Doddsie]

If two snakes get hold of each others tail and keep swallowing, whats left?? 

[stevierst]

Also, what's the square root of -1?

[Andy FZS]

Oh god I've just had a flash back to j notation and complex numbers, but these days although I can whistle the tune I often can't remember the words to most of my college stuff.:-\

[stevierst]

Or if you weigh a whale at a whale weigh station, where would you weigh a pie?

[ChristoT]

Also, what's the square root of -1?

I think i know. 

[Nosobrut]

If my fazer could travel faster than the speed of light would the head lights work , or is it all relative

[mr self destruct]

Like has been said before, it's the increased daytime an area gets that determines the season rather than the distance from the sun. The earth is between 91 and 94 million miles away from the sun, and incidentally, closest to the sun during our winter.

[Ebme Geek]

Not only the length of day but more the angle the radiation is hitting the ground, another version of what has been already said >>  shine a torch verticaly down onto the floor and you get a nice circle, now angle the torch over and you get a stretched circle covering a much larger area, but the same amount of energy in total, so each bit gets less heating effect.

I think i know. 

Could always express that in Polar notation
  And please nobody mention the 'frequencey domain'
  otherwise we will get into Fourier transforms  [img alt=:groan]http://foc-u.co.uk/Smileys/efocicon/groan.gif[/img] 

[caretaker]

42

[stevierst]

42

At last, a man that makes some sense. Bravo caretaker, bravo!! 8)

[midden]

Or if you weigh a whale at a whale weigh station, where would you weigh a pie?

What type of pie is it?

[midden]

Typing "why do we have seasons" into Google brings up a wealth of images to illustrate the point, as sometimes things can get lost in the explanation. I'm one who needs images to explain something so here's a link to one.


http://d1jqu7g1y74ds1.cloudfront.net/wp-...ations.jpg


Hope it helps

Perfect explanation